Heterogeneous growth responses of pancreatic ductal adenocarcinoma organoids to exogenous Wnt supplementation: an in vitro experimental study in Korea

Background: Pancreatic ductal adenocarcinoma (PDAC) exhibits substantial molecular heterogeneity, including classical and basal-like subtypes. However, whether extracellular signaling dependence varies according to subtype-associated molecular features remains unclear.Methods: PDAC cell line–derived spheroids and patient-derived organoids (PDOs) were cultured under Wnt-negative [Wnt(−)] or Wnt-supplemented [Wnt(+)] conditions. Spheroid and organoid size and morphology were assessed, and GATA6 expression was evaluated using publicly available transcriptomic data and digital droplet polymerase chain reaction.Results: Basal-like PANC-1 and MIA PaCa-2 spheroids showed impaired growth under Wnt(−) conditions and increased spheroid size following Wnt supplementation. In contrast, classical-type spheroids showed limited or variable responses. PDOs also exhibited heterogeneous Wnt responsiveness. GATA6 expression was enriched in classical-type cell lines but varied among PDOs. However, a direct association between GATA6 expression and Wnt responsiveness was not established.Conclusion: PDAC 3-dimensional culture models showed heterogeneous responses to exogenous Wnt supplementation. Cell line–derived spheroids showed a potential subtype-related pattern, although substantial model-specific variability was observed. Further molecular classification and mechanistic studies are needed to determine whether GATA6-associated cell states influence Wnt responsiveness.